1. Field of the Invention
This invention relates to undersea construction and more particularly it concerns novel methods and apparatus relating to breakwaters.
2. Description of the Prior Art
A breakwater is an elongated massive structure or formation in the sea, usually located near a coast, which rises above the surface of the sea to resist wave action. Thus while the sea may be rough with high waves on one side of the breakwater i.e. the seaward side, the water on the other side, i.e. the landward side, remains relatively calm. Breakwaters thus are used to form artificial harbors for allowing the docking and mooring of large sea going vessels.
In the past, breakwaters have been constructed by the application of fill material, e.g. stones, cement, boulders, etc., to a predetermined location on the sea bed, and continuing this application until there is built up a mound which rises from the sea bed to a predetermined height above the sea surface. Often this basic construction technique would be refined by the use of cribs, i.e. open framework structures, to contain the fill material. Also, poured concrete has been employed to provide well defined upper surfaces on the breakwater so that docking and unloading of vessels can be carried out.
Difficulties are experienced with prior breakwater structures where the sea bed on which a structure is to rest does not have substantial bearing strength. In such case the structure actually sinks down into the sea bed. Additional fill material is then required to build up the breakwater; but this adds further to its weight so that it sinks even deeper.